“Yeah,” says Sacks dreamily, sounding like a man who has experienced this ecstasy of first love again and again.

“Weisskopf, the physicist, wrote a book called The Joy of Insight,” he says, “which is very much along those lines. He was also a very good amateur musician and he had one chapter called ‘Mozart Quantum Mechanics,’ in which he tried to compare the joy of one with the joy of the other.”

“The joy of insight—does love have something to do with the joy of mutual insight? Two people having a special depth of insight into the other?”

“Well, one certainly can love when one feels this, when one is reaching to understand that depth which is very special,” he says.

Toward the end of our talk I ask Sacks what, after all his years investigating the mysteries of the mind, he still most wanted to know.

“More about how consciousness works and its basis, how it evolved phylogenetically and how it evolves in the individual.”

In part his answer has to do with the mystery of the “director” of consciousness, the self that integrates all the elements of perceptions and reflection into an “order-experience” of the world. How does this “director”—this “self”—evolve to take charge or “self-organize” in the brain, as some neuroscientists put it. And how does he or she lose control in hallucinations?

Another question of consciousness he wants to know more about is the mystery of consciousness in animals. “As a scuba diver I’ve seen plenty of cuttlefish and octopus. Darwin talks about this very beautifully in The Voyage of the Beagle. He sees an octopus in a tidal pool and he feels it watching him just as closely as he is watching it. And one can’t avoid that sort of impression.”

You’ve got to love Dr. Sacks’ insatiable curiosity, the sense that he is ready to fall in love again and again and that the insights never stop. What must being inside his brain be like? As I was leaving his office we had a final exchange that may provide a clue. We were talking about his own experience of hallucinations and hallucinogens and how he deplored the way the unscientific publicity show put on by the original LSD experimenters Timothy Leary and Richard Alpert (later named Ram Dass), and others, set back, indeed, made “serious research on these things impossible, and it’s only resumed really in the last decade,” he says. “LSD can mess with some of the highest orders, the highest sort of processes in the brain, and it’s important to have investigation which is ethical, lawful and deep and interesting.”

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